The Navitron Off
Course Alarm type NT925OCA is a fully independent course monitoring device
which complies with the articles of IMO resolution A342 (IX).

It can be installed
with a single heading input obtained from a Navitron Heading Sensor Coil
(type HSC2) or from a proprietary NMEA source (or both) when used as a
completely independent system. However, if one of the heading data inputs
is common to the heading data provided for an autopilot system (gyro data
etc) the second heading input to the NT925OCA must be obtained from an
independent (mag compass etc) source.

Model
NT925OCA
Off Course Alarm

Simple to operate, both versions feature: -

NT925OCA / 1 is primarily intended for use as an independently referenced course monitor which, when installed as an independent system or in conjunction with an appropriate
Navitron Autopilot system, renders the entire configuration compliant with all articles of IMO Resolution A.342(ix).

Dual Heading input ports are standard and can be connected to accept magnetic information derived from a Navitron heading sensor coil attached above or
below an existing ships compass and / or a range of NMEA 0183 heading
sentences derived from proprietary sources such as GPS compasses and Gyro’s
etc. Whilst only one heading input is essential, dual inputs will provide a back up
system where either input maybe chosen as the primary or secondary heading
reference.

Standard features include installation programmable Deviation and Variation
correction, NMEA 0183 and Step by Step (installation Programmable 3, 6,12
and 24 step/degree) heading outputs for use by proprietary radars etc.

NT925OCA / 2 is designed for use as an independently referenced Off Course Alarm but includes a Course Comparator Alarm which may be enabled or disabled
during installation as required.

Unlike the heading sensor coil and single NMEA input associated with the
NT925OCA / 1, the NT925OCA / 2 features dual NMEA 0183 heading input
ports. Only one input is required for Off Course Alarm operation whilst dual
inputs are essential for the additional Course Comparator function which
continuously monitors and compares the two sets of NMEA data received.
In the event of excessive differences between the data received (trip level installation programmable 1-20°) the alarm is activated.